1 /* 2 * Copyright (c) 2022, Red Hat, Inc. All rights reserved. 3 * Copyright Amazon.com Inc. or its affiliates. All Rights Reserved. 4 * Copyright (c) 2024, Oracle and/or its affiliates. All rights reserved. 5 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 6 * 7 * This code is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License version 2 only, as 9 * published by the Free Software Foundation. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 * 25 */ 26 27 #ifndef SHARE_RUNTIME_LOCKSTACK_HPP 28 #define SHARE_RUNTIME_LOCKSTACK_HPP 29 30 #include "oops/oopsHierarchy.hpp" 31 #include "utilities/globalDefinitions.hpp" 32 #include "utilities/sizes.hpp" 33 34 class JavaThread; 35 class OopClosure; 36 class outputStream; 37 template<typename> 38 class GrowableArray; 39 40 class LockStack { 41 friend class LockStackTest; 42 friend class VMStructs; 43 JVMCI_ONLY(friend class JVMCIVMStructs;) 44 public: 45 static const int CAPACITY = 8; 46 private: 47 48 // TODO: It would be very useful if JavaThread::lock_stack_offset() and friends were constexpr, 49 // but this is currently not the case because we're using offset_of() which is non-constexpr, 50 // GCC would warn about non-standard-layout types if we were using offsetof() (which *is* constexpr). 51 static const int lock_stack_offset; 52 static const int lock_stack_top_offset; 53 static const int lock_stack_base_offset; 54 55 // The offset of the next element, in bytes, relative to the JavaThread structure. 56 // We do this instead of a simple index into the array because this allows for 57 // efficient addressing in generated code. 58 uint32_t _top; 59 // The _bad_oop_sentinel acts as a sentinel value to elide underflow checks in generated code. 60 // The correct layout is statically asserted in the constructor. 61 const uintptr_t _bad_oop_sentinel = badOopVal; 62 oop _base[CAPACITY]; 63 64 // Get the owning thread of this lock-stack. 65 inline JavaThread* get_thread() const; 66 67 // Tests if the calling thread is the thread that owns this lock-stack. 68 bool is_owning_thread() const; 69 70 // Verifies consistency of the lock-stack. 71 void verify(const char* msg) const PRODUCT_RETURN; 72 73 // Given an offset (in bytes) calculate the index into the lock-stack. 74 static inline int to_index(uint32_t offset); 75 76 public: 77 static ByteSize top_offset() { return byte_offset_of(LockStack, _top); } 78 static ByteSize base_offset() { return byte_offset_of(LockStack, _base); } 79 80 LockStack(JavaThread* jt); 81 82 // The boundary indicies of the lock-stack. 83 static uint32_t start_offset(); 84 static uint32_t end_offset(); 85 86 // Returns true if the lock-stack is full. False otherwise. 87 inline bool is_full() const; 88 89 // Pushes an oop on this lock-stack. 90 inline void push(oop o); 91 92 // Get the oldest oop from this lock-stack. 93 // Precondition: This lock-stack must not be empty. 94 inline oop bottom() const; 95 96 // Is the lock-stack empty. 97 inline bool is_empty() const; 98 99 // Check if object is recursive. 100 // Precondition: This lock-stack must contain the oop. 101 inline bool is_recursive(oop o) const; 102 103 // Try recursive enter. 104 // Precondition: This lock-stack must not be full. 105 inline bool try_recursive_enter(oop o); 106 107 // Try recursive exit. 108 // Precondition: This lock-stack must contain the oop. 109 inline bool try_recursive_exit(oop o); 110 111 // Removes an oop from an arbitrary location of this lock-stack. 112 // Precondition: This lock-stack must contain the oop. 113 // Returns the number of oops removed. 114 inline size_t remove(oop o); 115 116 // Tests whether the oop is on this lock-stack. 117 inline bool contains(oop o) const; 118 119 // GC support 120 inline void oops_do(OopClosure* cl); 121 122 // Printing 123 void print_on(outputStream* st); 124 }; 125 126 #endif // SHARE_RUNTIME_LOCKSTACK_HPP --- EOF ---